Most of you will be aware that with v1.53 (1st August), AC changed its Asset Store category to Editor Extensions, bringing with it several UX advantages - but also changed the license agreement to one-per-seat.
At the time, I stated that while this would not affect existing projects, it would affect new projects by existing customers. Due to a miscommunication between myself and Unity, I was mistaken and this is not the case. Those who purchased AC before 1st August 2016 can continue to use AC with the
same license that AC had at the time of purchase.
I apologise for the error and confusion - it was far from my intent. If you were such a customer, who bought additional licenses on the basis of this error, please PM me so that we can resolve issues on a case-by-case basis.
Thanks, and happy AC-ing!